scholarly journals A Sine Curve Crack in Natural Ice

Nature ◽  
1935 ◽  
Vol 135 (3421) ◽  
pp. 877-877
Author(s):  
PAVEL GROSELJ
Keyword(s):  
2018 ◽  
Vol 230 (1) ◽  
pp. 319-331
Author(s):  
Peishi Yu ◽  
Jiawang Sun ◽  
Chaofeng Zhang ◽  
Junhua Zhao

1971 ◽  
Vol 61 (1) ◽  
pp. 167-176 ◽  
Author(s):  
Harsh K. Gupta ◽  
B. K. Rastogi ◽  
Hari Narain

abstract The analysis of P waves recorded at seismological observatories and seismic arrays at teleseismic distances and strong motion seismographs located at Koyna Dam suggest the Koyna earthquake of December 10 1967 to be a complex multiple event. Six of the events could be identified, and the second and third events are located with respect to the initiation using the Gutenberg sine-curve method at distances of 6 and 17 km due south, the average rupture velocity being 3.4 km/sec. The findings are consistent with the field observations and the different origin times, epicenters and magnitudes reported for the earthquake. Seismic array records are found to be very useful in examining the multiplicity of seismic events.


2019 ◽  
Vol 23 (8) ◽  
pp. 3423-3436 ◽  
Author(s):  
Scott T. Allen ◽  
Scott Jasechko ◽  
Wouter R. Berghuijs ◽  
Jeffrey M. Welker ◽  
Gregory R. Goldsmith ◽  
...  

Abstract. Quantifying seasonal variations in precipitation δ2H and δ18O is important for many stable isotope applications, including inferring plant water sources and streamflow ages. Our objective is to develop a data product that concisely quantifies the seasonality of stable isotope ratios in precipitation. We fit sine curves defined by amplitude, phase, and offset parameters to quantify annual precipitation isotope cycles at 653 meteorological stations on all seven continents. At most of these stations, including in tropical and subtropical regions, sine curves can represent the seasonal cycles in precipitation isotopes. Additionally, the amplitude, phase, and offset parameters of these sine curves correlate with site climatic and geographic characteristics. Multiple linear regression models based on these site characteristics capture most of the global variation in precipitation isotope amplitudes and offsets; while phase values were not well predicted by regression models globally, they were captured by zonal (0–30∘ and 30–90∘) regressions, which were then used to produce global maps. These global maps of sinusoidal seasonality in precipitation isotopes based on regression models were adjusted for the residual spatial variations that were not captured by the regression models. The resulting mean prediction errors were 0.49 ‰ for δ18O amplitude, 0.73 ‰ for δ18O offset (and 4.0 ‰ and 7.4 ‰ for δ2H amplitude and offset), 8 d for phase values at latitudes outside of 30∘, and 20 d for phase values at latitudes inside of 30∘. We make the gridded global maps of precipitation δ2H and δ18O seasonality publicly available. We also make tabulated site data and fitted sine curve parameters available to support the development of regionally calibrated models, which will often be more accurate than our global model for regionally specific studies.


2011 ◽  
Vol 291-294 ◽  
pp. 286-289
Author(s):  
Jian Ren Sun ◽  
Chi Bing Hu

Control of the motion process of acceleration/deceleration (Acc/Dec) is one of key complicated problems in CNC system development. The excellent Acc/Dec control can improve the processing precision. The traditional Acc/Dec algorithms such as the linear and the exponential are not suitable for high speed motion because there would be flexible impacts existing in feed motion, especially that the jerk of the S-shape curve Acc/Dec is discontinuous. A new flexible Acc/Dec algorithm for high speed motion system based on the squared sine function is introduced. The modeling of the Acc/Dec algorithm with Trigonometric Function Squared Sine(TFSS) shape curve is constructed.In this algorithm, the sine curve in jerk, acceleration, velocity and displacement are all continuous. The simulation experiments result demonstrate that the Acc/Dec algorithm with TFSS shape curve is a new method of continuous Jerk for the design flexible Acc/Dec.


2013 ◽  
Vol 437 ◽  
pp. 382-387
Author(s):  
Guo Ping Zhao ◽  
Yuan Xun Fan ◽  
Feng Yang ◽  
Li Yi Li

Base on analyzing the design demand of the return system in the ball screws, combining the sine curve and the quintic parabola curve, this paper introduces a new type of curve for steel balls used in heavy load bearings. By computing and programming in Matlab, this paper gets the sine-quintic parabola curve and conducts the kinematic simulation based on it. The results show that the balls can get in and out of the return system continuously and cause low impulse force on the return system. The highest impulse force happens when the balls access the return system. All this results can contribute for the later design and research of the internal circulation return system.


2014 ◽  
Vol 1027 ◽  
pp. 302-305
Author(s):  
Xiao Ming Han ◽  
Dong Sheng Li ◽  
Long Lie Zhang ◽  
Xing Yu Han

Through the condition analysis of the drill rod during the mining horizontal drilling for gas drainage, the finite element model of the drill rod lateral vibration is established. The drill rod lateral vibration is related to the diameter and length of the drill rod. With the increase of the diameter of the drill rod, the natural frequency of the lateral vibration of the drill rod increases constantly. The increasing amplitude of the natural frequency at the larger diameter of the drill rod is larger than that at the smaller diameter. When the drill rod is longer, the natural frequency of the lateral vibration of the drill rod is lower. From the modal images of the drill rod, the lateral vibration of the drill rod is similar to the sine curve. During the horizontal drilling in coal seam, the drill rod contact and impact with the hole wall which will bring about the fatigue fault of the drill rod and the collapse of the hole wall.


1968 ◽  
Vol 61 (4) ◽  
pp. 391-392
Author(s):  
David Paisley

I was having some difficulty with a transparency (Fig. 1) that I had made for my trigonometry class. The transparency had a tendency to curl and roll into a cylindrical shape. I then noticed that if the cylinder were twisted to a particular size, the sine curve wrapped around the cylinder in a shape that resembled an ellipse (Fig. 2). To obtain this particular size, the cylinder was twisted so that the points labeled K matched, and the points labeled O matched. The sine curve wrapped around the cylinder about three times on the particular model I had.


1944 ◽  
Vol 44 (5) ◽  
pp. 467-468
Author(s):  
Walter V. Burg
Keyword(s):  

1949 ◽  
Vol 33 (306) ◽  
pp. 300
Author(s):  
H. F. Sandham
Keyword(s):  

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